A liquid crystal display (LCD) is a flat panel displaying device that is made up of a certain number of segments filled with liquid crystals and arrayed in front of a light source or a reflector to produce images in color or monochrome. Compared with traditional display based on a cathode ray tube (CRT), the LCD is more energy efficient and safer, and thus has become the mainstream in the market.
The LCD includes a backlight module, a liquid crystal layer, a polarizer, and color filter layers. Grayscale and brightness of each pixel are controlled by adjusting a polarization direction of a backlight through the liquid crystal layer and filtering the backlight with a different polarization direction with polarizers. Then, a light of desired color is generated by filtering unwanted components of the backlight with the color filter layers. However, many components of the backlight which may be not unwanted are also filtered, such that the brightness of the LCD becomes much weaker than that of the original backlight. For a high pixel per inch (PPI) LCD, if the brightness of the high PPI LCD is enhanced, its comprehensive performance may be significantly improved accordingly.
Further, a high efficiency backlight module of the LCD usually uses a blue light-emitting diode in association with a yellow phosphor layer. Afterwards, a blue light from the blue light-emitting diode and a yellow light from the yellow phosphor layer mix with each other and become a yellowish white light. Such backlight module requires a display panel having a special electrode design for adjusting the yellowish white light to achieve the best optical match.